how to make a tangent ball to a cylinder

[iron72]

Hello.
I am trying to make a tube in with the surfaces and in the final part I have to close it with a ball, only that if I bend too much the director that I built with a spline, the tube bends too much and the ball does not appear tangent the tube itself but remains like a hump.
Does anyone know how to handle this?
Thank you.
p.s.: here is the file made in r17

 

[alexfunk]

Hello.
I am trying to make a tube in with the surfaces and in the final part I have to close it with a ball, only that if I bend too much the director that I built with a spline, the tube bends too much and the ball does not appear tangent the tube itself but remains like a hump.
Does anyone know how to handle this?
Thank you.
p.s.: here is the file made in r17

If you want the ball to be tangent,the start of the guide curve must be perpendicular to the sketch of the tube profile.
Hello alexfunk